Electrical connectors are frequently attached to a substrate, such as a printed circuit board (PCB), using a Ball Grid Array (BGA) type of electrical connection. The BGA includes a plurality of solder balls that are used to connect electrical contacts of the connector to the PCB. A typical BGA connector is connected to an array of electrical contact pads or traces disposed about the surface of the substrate. The solder balls are attached to the contact pads by first applying a resin flux to the electrical contact pads, positioning the solder balls onto the electrical contact pads, and running the connector through a reflow furnace. During the reflow process the solder balls are held in position by the flux and wetted onto the electrical contact pads. In addition to holding the solder balls in position, the flux promotes the wetting of the solder balls to the contact pads and chemically cleans the contact pad surfaces.
However, the small solder balls in a BGA connection produce only a short connection height between the electrical contacts of the connector and the contact pads of the substrate. These short connections are subject to high mechanical stress if any movement occurs between the connector and the substrate. As a result, the connection between the connector and the substrate is vulnerable to failing as a result of the solder connection breaking due to stress.
One approach to apply solder balls on the contacts involves reflowing solder, placing the liquid solder on the contact, and allowing the solder to cool to form a ball disposed on the contact. However, this is a very complex and time consuming process. The requirement to heat and cool the solder as it is applied to the contacts can be time consuming.